Non-inflammable cellulose compound and process of making the same.



UNITED STATES PATENT OFFICE.

WILLIAM G. LINDSAY, 0F NEWARK, NEW JERSEY, ASSIGNOB TO THE OELLULOIDCOMPANY, A CORPORATION OF NEW JERSEY.

NON-INFLAMMABLE CELLULOSE COMPOUND AND PROCESS OF MAKING THE SAME.

Specification of Letters Patent.

Patented Nov. 6, 1917.

No Drawing. Original application filed September 10, 1912, Serial No.719,543. Divided and this application filed January 27, 1915. Serial No.4,676.

To all whom it may concern:

Be it known that I, WILLIAM G. Lmosar, a citizen of the United States,residing at Newark, in the county of Essex and State of New Jersey, haveinvented certain new and useful Improvements in Non-InflammableCellulose Compounds and Processes of Making the Same, of which thefollowing is a full, clear, and exact specification.

This invention relates to a new composition of matter which isnon-inflammable, and which possesses permanently great strength andtenacity, and can be used as a substitute for nitro-cellulosecompositions such as celluloid and similar substances, and also to theprocess of maki the same. The present application is a. dlvision of myapplication No. 719,543, filed September 10, 1912, which has eventuatedinto Patent No. 1,199,798, Oct. 3, 1916.

Heretofore, it has been proposed to substitute acetyl cellulosefor'nitro-cellulose in the manufacture of compounds of which celluloidis a prominent example. But, so far as I am now aware, such compoundshave been unsuccessful, principally for the reason that the compoundswere not sufficiently strong and not sufiiciently tenacious, whetherobtained by evaporation from a solution or by manipulating a lastic mam,nor have they been non-in ammable.

I have discovered that triphenylphosphate can be combined with acetylcellulose to produce a non-inflammable compound having great strengthand tenacity, and other valuable properties, and the present inventionis designed to point out to the operator a practical method of using orcombining these two substances in'making films and other forms of suchcompounds. So far as I know, I am the first to successfully usetriphenylphosphate with acetyl cellulose, and also the first to discoverthe method of making a useful product or compound containing acetylcellulose and triphenylphoshate. p In carrying out my invention, Iselect an acetyl cellulose which is soluble in acetone, a solution ismade of such acetyl cellulose in acetone and to this solution is addedtriphenylphosphate, either in solid form or previously dissolved inacetone or other similar solvent. I also add 10 to 24 parts ofdichlorhydrin' (or its hereinafter specified equivalent). The amount oftriphenylphosphate may be varied in proportions from ten to twenty partsby weight to each one hundred parts of the acetyl cellulose, and

the acetone or other suitable solvent is added in sufiicient quantity tomake either a flowable solution or a plastic mass, as is well understoodby those skilled in the art; but I do not limit myself to any specificpro ort1ons because they may be diminishe or increased as desired.

The addition of triphenylphosphate increases both the strength andtenacity and also insures non-inflammability. This increase in strengthand tenacity may, as I have found by experiment, be secured in greateror less degree by substances which are to a large extent equivalents oftriphenylphosphate, such as diphenylamin, trichlorphenol,tricresylphosphate, and, to a lesser extent, phenolsalicylate. I prefer,however, the triphenylphosphate because, while it imparts anon-infiammability t0 the compound, it does not impart any color or odorto the product. Again, as indicated, I may use other menstrua orsolvents than part or all of the acetone, such, for instance, aschloroform, ethyl acetate or acetylene tetrachlorid, which, either aloneor when two of them are mixed together, are capable of dissolving theacetyl cellulose in the presence of triphenylphosphate or othersubstances indicated above. I have also found that it may be useful insome cases to use alcohols in the solvent mixture both for the urpose ofcausing fluidity and for regulating the evaporation of the solvent.

A further advantage in the case of some of the heavy or high boilingsolvents arises from their property of restraining or decreasing ormodifying the volatility of the mixture and thus increasing the tensilestrength and elasticity of the resultant product; acetylenetetrachlorid, when used alone, or with chloroform, alcohol, ethylacetateor the like, in varying proportions is especially useful in thisconnection. In place of dichlorhydin, I may use diacetic ether, benzoicether, aceto-dichlorhydrin, or any slowly volatile solvent of acetylcellulose which is capable of dissolving or liquefyingtriphenylphosphate. or its specified equivalent, in the presence ofacetyl cellulose. By preference, however, I use dichlorhydrin, for itsaction exemplifies in the highest possible manner the combinationprinciples referred to.

By the addition of about 1% of urea, still greater permanency andtenacity will be imparted to my'compound. The proportion of urea orequivalent substance will vary according to the desired degree ofincreased strength and the stability of final product. A proportion oftwo parts urea to one hundred parts of the cellulose compound gives mostexcellent results; a less proportion 15 sufficient for ordinarypurposes. I have obtained satisfactory results with a proportion of ureaas low as one part to one hundred parts of the cellulose compound.

For certain purposes, it is advantageous to ma'ke a thorough mechanicalmixture containing the acetyl cellulose and triphenylphosphate, orequivalent substances, and subsequently add the solvent or liquidmenstruum.

The product ma'de in accordance with my invention can be made in theform of films or thin sheets. Any approved method of forming films orthin sheets from a flowable solution may be employed. It will beunderstood, also, that the flowable solution formed as above describedmay be applied as a protectin surface, such a coating possessing also te property of being waterproof. The final product may also be made inthe form of a mass of any' desired thickness. It will be obvious thatsuitable pigments or coloring matter may be added to the above mixtureor solution to produce final product for use in imitating othersubstances, such as amber, ivory, horn, marble, or the like.

Having thus described my invention, what I declare as new and desire tosecure by Letters Patent of the United States, is

1. A composition including acetyl cellulose, acetone, chloroform and avolatility decreaser.

2. A composition including acetyl cellulose, a solvent therefor,chloroform and a volatility decreaser.

3. A composition of matter containing an organic derivative ofcellulose, and a nonin ammable material which is insoluble in water butsoluble in chloroform, obtained by dissolving them in chloroform and ahigh-boiling liquid insolublein water.

4. A composition of matter containing an organic derivative of celluloseand triphenylphosphate obtained by dissolving them in chloroform and ahigh-boiling. liquid insoluble in water.

5. A composition of matter containing an organic derivative of celluloseand triphenylphosphate obtained by dissolving them in chloroform, anddichlorhydrin.

In testimony whereof I afiix my signature, in presence of two witnesses.

WILLIAM G. LINDSAY.

Witnesses:

ADARENA PFEIFFER, I Jrssm MICKENB.

